Edu-Linguistic-English-IPA-英语发音：Vocal anatomy, muscles and function

https://web.uvic.ca/ling/resources/ipa/charts/IPAlab/IPAlab.htm
https://www.internationalphoneticassociation.org/IPAcharts/IPA_chart_orig/IPA_charts_E.html
https://www.internationalphoneticassociation.org/sites/default/files/phonsymbol.pdf
https://www.oxfordsinginglessons.co.uk/wp-content/uploads/2016/09/Vowels_vowel_sounds-v5-Massey.pdf

http://web.uvic.ca/ling/data/IPAlab/
https://web.uvic.ca/ling/resources/ipa
https://www.uvic.ca/humanities/linguistics/resources/software/ipaphonetics/index.php
https://www.uvic.ca/humanities/linguistics/resources/software/index.php

https://www.oxfordsinginglessons.co.uk/my-approach/the-four-core-areas/

https://alexandermassey.com

https://britishvoiceassociation.org.uk